Controller for electric elevators



March 27, 1928. 1,664,269

E. w. SEEGER CONTROLLER FOR ELECTRIC ELEVATORS Orizinal Filed April 8. 1926 2 Sheets-Sheet 1 IN VEN TOR.

ATTORNEY March 27, 1928.

E. W. SEEGER CONTROLLER FOR ELECTRIC ELEVATORS Original Filed April 1926 '2 Sheets-Shoot 2 EIII'II" FDR INVENTOR. 5M nag/aw. BY 2 2 22 ATTORNEY.

Patented Mar. 27, 1928. UNITED STATES PATENT OFFICE.

EDWIN W. SEE-GER, OF SOUTH MILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER- HAMMER MFG. 00., OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

CONTROLLER FOR ELECTRIC ELEVATORS.

Application filed April 8, 1926, Serial No. 100,747. Renewed August 29, 1927.

This invention relates to controllers for mally closed auxiliary contacts 18, and moveelectric elevators, and more particularly to ment of said relay in either direction for automatic push button controllers for eleopening or closing said contacts is retarded vator systems of the three landing type. by means of a double-dashing dashpot, as

An object of the invention is to provide shown. The shunt field SHF of the motor improved and simplified control means of is adapted to be connected across the line in the above character. parallel with the shunt coil SHB of a suit- Another and more specific object is to proable brake (not shown) upon closure of vide improved electrical interlocking means the normally open contacts 19, 20 and21 of H! for preventing interference when control electro-responsive switch FB, as hereinpush buttons are simultaneously operated after more fully described. A field diswithin the car and on a landing, with the charge resistance FDR may also be proelevator car at the middle landing. vidcd in parallel with the shunt field.

Another object is to provide a novel com- As aforeindicat-ed the present invention )5 bination of electrical relays to insure proper is particularly adapted for automatic confunctioning of the various control elements. trol of an elevator system of the three land- Other objects and advantages of the ining type, wherefore I have provided three vention will hereinafter appear. landing door switches DS DS and DS',

The accompanying drawing illustrates an each of said switches being adapted to be so embodiment of the invention which will now closed or opened, depending upon closure or be described, it being understood that the emopening of its respective landing door (not bodiment illustrated is susceptible of modishown), the arrangement being suchthat the fication without departing from the scope of elevator car cannot be operated for movethe appended claims. ment in either direction unless all of the :5 In the drawing, Figure 1 is a schematic landing doors are in closed position.

and diagrammatic view of a controller em- Arranged at suitable points in the elebodying the invention; and va'tor shaft or hatchway arev a plurality of Fig. 2 is an across-the-line diagram of switches adapted to be operated by a cam C the controller illustrated in Fig. 1. or other fixed portion of the car. The

Referring to Fig. 1, A indicates the armaswitch indicated at DOT is adapted to pre- 55 ture of a direct current motor to be supplied vent overtravel of the car in a downward with current from lines L L single-pole direction, through opening of its normally electromagnetic switches D, D and U U closed contacts 22. Switch DS is adapted being provided for establishing reverse to effect stopping of the motor and conse- 35 power connections for the motor, the quently of the car, when the latter in travelswitches D and 1) providing for operation ing downward is in proper position with of the motor in one direction and the respect to the bottom floor or landing, due switches U andU providing for reverse opto opening of the normally closed contacts oration thereof. Switch D is provided with 23 thereof. Switch MLD is arranged to 40 normally open auxiliary contacts 10, 11 and effect stopping of the carat the middle land- 12, whereas switch D is provided with noring, under certain conditions, when the car mally closed auxiliary contacts 13. Switch is moving downwardly from the top or up U is likewise provided with normally closed per landing, upon opening of its contacts 24, auxiliary contacts 14, whereas switch U is said contacts being biased by means of spring 45 provided with normally open auxiliary con- 25 to closed position but are held and locked tacts 15, 16 and 17. in open position under certain conditions, as

The motor may be of the compound-wound hereinafter more fully described. Switch type, the series field thereof being indicated MLU is similarly arranged to effect stopping at SF. In series with the armature A are of the car at the middle landing, under cer- 50 a number of sections of accelerating resisttain conditions, when the car is moving up 106 ance R, R, R and R, a relay AR being wardly from the bottom or lower landing adapted when energized to effect gradual upon opening of its contacts 26, said conexculsion of said resistance sections and being taots being also biased to closed position by also adapted to finally short-circuit the series spring 27 but are held and locked in open 55 field Relay AB is provided with norposition, as shown, under certain conditions 110 ill ill

hereinafter let forth. Switch US is adapted to effect stopping of the motor and conse quently of the car, when the latter in traveling upward is in proper position with re spect to the top floor or landing, due to opening of the normally closed contacts 28 thereof. Switch UOT is adapted to prevent overtravel of the car in an upward direc tion, through opening of its normally closed contacts 29.

Push button s itches L L and if, located at the bottom, middle and top landings, respectively, are adapted when depressed to direct and control movement of the car to the corresponding floor or landing; switch L being provided with normally open down contacts, whereas switches if and are each provided with normally open down contacts and normally closed up contacts. Push button switches U, C and G located within the elevator car, are each provided with normally open down contacts and normally closed up contacts, said switches being likewise operable to direct and control movement of the car to the several landings. Also located within the car is a Stop push button,-the latter being operable to effect stopping of the car at any desired point in its travel, The car door switch CS is adapted to prevent movement of the car from any position thereof prior to closure of the car door. I

A relay Mlilt is provided, which comprises normally open main contacts 30 and 31 and normally closed auxiliary contacts 32 and 33, the operating winding of said relay being adapted to be energized only upon depression of the landing push button L or the car push button C for calling or directing the car to the middle landing of the ele vator shaft.

The operation of the controller will now be described with particular reference to the simplified diagram shown in Fig. 2. Assuming the elevator car to be at the bottom or lower landing, with the car door closed and each of the landing doors closed, and further assuming that it is desired to call the car to the top or upper landing,the push button L is depressed, thereby providing an ener= gizing circuit for the operating windings of switches U and U This circuit may be traced. from line L through contacts 22 of switch DOT and contacts 29 of switch UGT, thence through auxiliary contacts 13 of switch D and auxiliary contacts 14; of switch U thence through the respective up contacts of push button switches C C and C thence through the down contacts of push button switch L and through the windings of switches U and "U in parallel, thence through contacts 28 of switch US and normally closed auxiliary contacts 33 of relay MLR, through the winding of switch lElB, contacts GS of the car door switch and the normally closed contacts of the top push button switch, thence through the contacts of landing door safety switches BS D8 and DS, and through normally closed contacts 18 of switch Alt to line L. Switches U and U are thus closed to provide an energizing circuit for the motor which circuit may be traced from line L through the contacts of switch U through the armature A and the contacts of switch U thence through series field SF and through resistance sections R R R and in seriesto line L.

Upon closure of the normally open auxiliary contacts of switch U a maintaining circuit is provided for the windings of said switch and switch U which circuit extends from line D through contacts 22 and 29, as aforedescribed, thence by conductor 8i through auxiliary contacts 15 and 17 of switch U thence by conductor through the windings of switches U and U in paral lel, and thence to line L in the manner pre viously traced; whereas switch U in closing effects opening of its auxiliary contacts 14-,

thereby disconnect-ing all push button control stations from the line, except the Stop button, pending travel of the car through the range pie-selected which results in opening of contacts 28 of hatchway limit switch US to interrupt the circuits aforedescribed, thus bringing the car to rest at the upper landing.

As indicated in the drawing the auxiliary contacts i l of switch U are so constructed and arranged that they will remain closed for an interval of time after closure of the auxiliary cont-acts of switch U to provide for establishment of the maintaining circuit aforedescribed; whereas ihe'auxiliary contacts 13 of switch D are similarly construct ed and arranged so that they will remain closed for an interval of time after closure of the auxiliary contacts of switch D as hereinafter more fully described.

Also upon closure of the auxiliary con facts of switch U an energizing circuit is provided for the operating winding of relay Alt, said circuit extending from line L to contact 15, as heretofore traced, thence to contact 16,- and by conductor 36 through the winding of said relay to line L Closing movement of accelerating relay AR is retarded in the manner aforedescribed, thus gradually bringing the motor up to speed, whereas the auxiliary contacts 18 of said relay are opened to include the resistance section a; in circuit with the windings of switches U U and FE to permit holding energization thereof, while preventing oper ating energization of said windings, or of the windings of switches D and D for predetermined period after interruption of the first mentioned energizing circuit. This is due to the provision of the dual-pet on llll relay AR which retards the reclosing movement of the auxiliary contacts 18.

The party who has called the car to the top landing is therefore given sufiicient time after arrival of the car to open the landing door, with consequent opening of switch Ds prior to closure of said auxiliary contacts 18. After entering the car and closing the top landing door and the car door, the occupant may dispatch the car to the middle or the bottom landing by operating the switch C or C, respectively.

As will be apparent, if the car were dis patched to the top landing, by a party in the car at the bottom landing through operation of the switch C the control system would function in a manner similar to that just described, a similar energizing circuit being thus completed which would extend from line L through the down contacts of push button switch C by conductor 37 through the windings of switches U and U in parallel, and thence to line L as previously traced.

The aforementioned. operation of the car push button switch C (with the car at the top landing) would complete an energizing circuitfor the winding of relay MLR, said circuit extending from line L to and through the up contacts of push button switch C as heretofore traced, thence through the down contacts of switch C by conductor 38 through the winding of relay MLR, thence by conductor 39 through contacts CS, and to line L as previously traced.

Operating energization of the winding of relay MLR effect-s closure of the main contacts 30 and 31 thereof and simultaneous opening of the auxiliary contacts 32 and 33. The cam operated switches MLD and MLU are provided with mechanical interlocking means whereby either of the contacts 24 and 26, respectively, may be opened while the other remains closed, or both of said contacts may be simultaneously opened; but if one of said contacts is closed the other contact will be automatically locked in open position.

Thus with the car at the top landing contact 26 will be locked in open position as illustrated, whereas contact 24; will then be in closed position, so that upon closure of contact 31 in the manner aforedescribed an energizing circuit will be provided for the operating windings of switches D and D said circuit extending from line L to conductor 38 as last traced, thence by conductor 42 through said contact 31, by conductors 13 and 44 through said windings D and D in parallel, through normally closed contact 23 of switch DS, by conductor 45 through closed contact 24, and thence by conductors 40 and 41 through winding FB to line L as heretofore traced.

Switch D in closing effects closure of its normally open auxiliary contacts 1.0, 11 and 12 thereby providing a maintaining circuit for the windings of switches D D and FE, said maintaining circuit extending from line L through contacts 22 and 29, by conductor 46 through auxiliary contacts 10 and 12, by conductor 47, and thence by conductor 44 through said windings to line L as just traced. A maintaining circuit for the winding of relay MLR is likewise provided, said maintaining circuit extending from line L' to conductor 417 as last traced, thence by conductor 43 through contact 31, by conductor 42 through said winding, and by conductor 39 through contacts OS to line L as heretofore traced. Closure of said auxiliary contacts also provides an energizing circuit for the winding of relay AR, said circuit extending from line L to auxiliary contact 10, thence through contact 11, by conductors 48 and 36 through said winding to line L".

The motor is thus started and accelerated to effect movement of the car in a downward direction, whereas upon downward movement of the car to a position wherein the cam C effects opening of contact 24 the maintaining circuits of the windings of switches D D and FB and the maintaining circuit of the winding of relay MLR will be interrupted, and consequently the motor will be stopped when the car is properly positioned at the middle landing.

As aforeindicated the normally closed auxiliary contacts 13 of switch D remain closed for a sufficient period after complettion of the energizing circuit of the latter to permit completion of the aforedescribed maintaining circuits through closure of the normally open auxiliary contacts of switch D With the car at the middle landing the same may be dispatched or called to the top landing by momentarily depressing the car push button switch C or top landing push button switch L respectively; or the car may be dispatched or called to the bottom landing by momentarily depressing the car push button switch C or bottom landing push button switch L.

' Thus, asssuming depression of push button switch C an energizing circuit is provided for the windings of switches D and D, said circuit extending from line L through normally closed contacts 22, 29, 1.3 and 14 and through the normally open down contacts of switch C by conductors 49, 50 and 44- through said windings, thence through the normally closed contacts 23 of switch DS and the normally closed auxiliary contacts 32 of relay MLR, and by conductors 51 and 41 through the winding of switch FB to line L as previously traced. A maintaining circuit will be provided for the windin s of switches D and D through closure of the lIiO 4, neeenee auxiliary contacts 10 and 12 of switch D and an energizing circuitwill be provided for the winding of relay Alt, in the manner heretofore described.

The motor will thus be operated to effect movement of the car in a downward direction, whereas upon engagement of the cam C with the operating element of switch DS the normally closed contacts 23 of the latter will be opened, thereby interrupting the energizing circuit of the windings D and D to bring the car to rest at the bottom landing.

It will be noted that upon movement of the car from the top or middle landing to the bottom landing the cam C on the car acts to ermit closure of contacts 26 of switch MLU, thus locking contacts 24- of switch MLD in open position. Similarly upon movement of the car from the bottom or middle landing to the top landing cam G acts to permit closure of contacts 2 of switch MLD, thus locking contacts 26 of switch MLU in open position. In this manner positive control of the desired direction of travel of the car from any position thereoj is insured. Moreover, by the arrangement aforedescribed non-interference between the car push button control stations and the landing push button control stations is in sured.

What I claim and desire to secure by Letters Patent is:

1. In a control system for electric elevators of the three landing type, the combination with means for effecting movement of the car from one landing to the other landings selectively, said means comprising a plurality of independently operable push button switches, means adapted upon temporary closure of one of said push button switches to effect operating energization of electroresponsive switches for effecting movement of the car in a predetemined direction, means adapted upon operation of said electroresponsive switches respectively to provide a maintaining circuit for the latter independently of said push button switches, and associated means also adapted upon operation of said electroresponsive switches to simultaneously disconnect all of said push. buttonswitches from the line pending movement of the car to the position preselected by closure of said first-mentioned push button switch.

2. In a controller for electric elevators of the three landing type, the combination with a plurality of push button switches for directing movement of the car to the respective landings, means controlled by certain of said switches for eltecting movement of the car to the middle landing, said means comprising a relay having a winding adapted to be energized only upon closure of one of said last mentioned switches, a plurality of sets of contacts controlled by said relay, elect-rd responsive switches the windings of which are respectively adapted to be connected in circuit with one of said sets of contacts, means dependent upon the position of the car with respect to the middle landing for efi'ect-ing completion of a circuit for the windings of said electroresponsive switches selectively, said means comprising a plurality of switches independently biased to closed position, independent operating means for said. switches located in the path of the car, and interlocking means for insuring against simultaneous closure of said switches.

3. In a controller for electric elevators of the three landing type, the combination with a car and an electric motor for driving the same, electroresponsive switches adapted when energized to complete circuit for the motor for effecting operation thereof in opposite directions selectively, push button control switches for initially completing the energizing circuits of said electroresponsive switches, auxiliary contacts on the latter adapted to provide maintaining circuits therefor, hatchwa-y limit switches in the path of the car for interrupting said maintaining circuits when the car reaches the top or bottom landing respectively, a plurality of independently operable switches in, the path of the car at the middle landing of the elevator, means for rendering said last mentioned switches effective for stopping the car at the middle landing, said means comprising a relay having a winding adapted to be energized upon closure of certain of said push button switches, contacts controlled by said relay, said contacts being respectively adapted to provide maintaining circuits for the winding of said relay and for said electroresponsive switches selectively, and means for rendering said maintaining circuits subject to control by said middle landing switches to thereby insure interruption of said circuits upon positioning of the car at the middle landing.

4:. In a control system for electric elevators of the three landing type,.the combination with means for edecting movement of the car toward the middle landing, of means operable under given conditions to effect automatic stopping of the car at the middle landing, said means comprising a plurality of switches independently biased to closed position, one of said switches being operable directly by the car when the latter is moving upwardly and the other of said switches being operable directly by the car when the latter is moving downwardly, and mechanical interlocking means for insuring open positioning of either 01 said switches when the other is in closed position.

5. In a control system for electric elevators of the three landing type, the combination with means for effecting movement of the ear toward the middle landing, of means operable under given conditions tc efi'ect automatic stopping of the car at the middle landing, said means comprising a plurality of switches independently biased to closed position, one of said switches being operable directly by the car when the latter is moving upwardly and the other of said switches being operable directly by the car when the latter is moving downwardly, and mechanical interlocking means for insuring open positioning of either of said switches when the other is in closed position, said last-mentioned means being also adapted to permit simultaneous opening of both of said switches.

6. In a control system for electric elevators of the three landing type, the combination with push button control means for effecting movement of the car in either direction toward the middle landing, of means dependent upon the direction of travel of the car to effect automatic stopping thereof at the middle landing, said means comprising a pair of switches independently biased to closed position and mechanical interlocking means for insuring open positioning of either of said switches when the other is in closed position, said last-mentioned means being also adapted to permit simultaneous open positioning of both of said switches, integral operating means for the respective switches located in the path of the car and adapted to permit closure of the switch first disengaged by the car when the latter is moving in one direction and to insure opening of said switch during movement of the car in the reverse direction, and additional push button control means for efiecting movement of the car in reverse directions past the middle landing while positively neutralizing the aforementioned stopping means.

7. In a controller for electric elevators of the three landing type, the combination with a car and a driving motor therefor, electroresponsive reversing switches for said motor, push button switches at the respective landings and corresponding push button switches within the car for selectively controlling the initial energizing circuits of said reversing switches, auxiliary contacts on the latter for maintaining the energizing circuits thereof independently of said push button switches, limit switches in the hatchway adjacent to the top and bottom landings for interrupting said energizing circuits respectively, a plurality of independently operable limit switches in the hatchway ad acent to the middle landing, means for rendering said last-mentioned limit switches effective for stopping the car at the middle landing, said means comprising a relay having an operat ing winding to be energized only upon closure of one of the push button switches corresponding to the middle landing, contacts controlled by said relay for rendering the energizing circuits of said reversing switches subject to control by said last-mentioned limit switches, means for insuring against closure of one of said last-mentioned limit switches when the car is above the middle landing, and means for insuring against closure of another of the same when the car is below the middle landing.

In witness whereof, I have hereunto subscribed my name.

EDWIN W. SEEGER. 

